Lumber straightening device



NV- 7 1933. H. H. PAYzANT ET AL LUMBER STRAIGHTENING DEVICE Filed Nov. 14, 1931 3 Sheets-Sheer. l

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Nov. 7, 1933. H. H. PAYZANT Er AL LUMBER STRAIGHTENING DEVICE Filed Nov. 14, 1931 3 Sheets-Sheet 2 SW1/low Zan? ue yz,

NOV- 7, 1933- H. H. PAYZANT Er AL 1,934,087

LUMBER STRAIGHTENING DEVICE Filed Nov. 14. 1931 3 Sheets-Sheet 3 i" ym gmantow /en H 79a zayz TALE! 38 @dal Luezliz Azo ovl

Patented Nov. 7, 1933 UNITED STATES or FICE n v 1,934,087'l v LUMBER STRAIGHTENINGLDEVICE Henry H. V.Payzant and Paul F. Luetln St. Paul,

Minn., assignors, by mesne assignments, to'V General Timberk Service, Inc., St. Paul, "Minn, a corporation of Delaware v Application November 14, 19312* Serial No. 575,035 l' 12 Claims. (C1. 143-49) LumberV frequently becomes bowed during the drying subsequent tothe sawing into straight pieces and Where itis accurately'trimmed at :both ends topredetermine'd lengths, each piece should beheld, during thetrimming, as nearlyas possible .with-its-longitudinal edgesin perpendicular relation to the trimming saws. Straightening of. the :lumber is. also important vduring :mai-king, asin cases where spaced lines, `extending transverse each piece, are applied to facilitate: measurements `in, construction ,.work.

Itis theobjectofthis inventionto provide -eiiicient meanszfor eliminating orA substantially reducing .the longitudinal-curve or ,bo win lumber,I during the trimming and/or 'marking without greatly increasing the cost of the product.

'A furtherobject is to .provide a machine of this kindadapted `to straighten indiscriminately mixed pieces of `lumber `which. ,vary` in thickness 2 0 vand width, the machine being designed to automatically adjust itself to pieces of differing Adimensions. 1

The invention will bebest understood by reference. to: the accompanying idrawings in which:

Figure lsis an endV -view cfa set of `the straightening. devices mounted on a vlumber rtrimming imachine; Y

, Figi 2 is a transverse section through the trimming-machine and showing one of `our straight- .1: SO-ening devices in side elevation;

Fig. 3 is a horizontal section;: through the straightening device, taken on the-,line 3 3 of `liigrZ;

FigA is an end view of the trimming machine :5.35. with theystraightening devices thereon;

above and parallelftoa table for the-,lumber .iormed by skids `13. Pieces-of lumber are indicated inthe drawings by Athenumeral 14. A Vtrimming sawY l5 is mounted near eachend of themachineV to trim the vends of the pieces of lumber Whichare conveyed edgewise or perpendicular to` their greatest dimension by suitable chain'conveyers. Each chain `conveyer,` consists of an endless chain ltrainedon sprocket wheels :.1553 irland` havingits upperfrungsupported .oni lat- Yframe members `are rsuslilended from ,hangers 28 ,ber 39 which -isperforated to slidably engagea j operative position relative tothe drum. ;A pix/9i erally projecting ilanges, integral with the skids 13. Each chain ,16 has lugs 18 secured theretoat `regularly ,spaced intervals. .Theselugsproject above the upper runof the chain,A to engage the lumber and `ihelugs on the several, chains'are disposed with their lumber-.engagingfaces yin alignment 'in rows extending perpendicular to he saws l5.

Qur straightening device has an `vendless chain 19 trained, on sprocket V:wheels 20 `and 2l.- At

4regularly spacedpoints ,lugsj22 project Afrom` the chain 19,r being providediwith contact .shoesj23 or engaging the lumber. The sprocketfwheels 2) and-21 are supported on horiZontalxshafts-Zfl and 25 respectivelyand theseashaitsrhave.suit- 70 able bearings secured toyopposite ends of A,ahorizontally extendingframe. Themain frame'members of the frame comprisea largeachannelmember 26 and a parallel anglermember, 27. :These having theirv upper ends lprojectingthrough perforations insupporting blocks 29. The hangers 28 are arranged topermit upward movement ofthe straighteningdevices when the thickerfpieces of lumber pass beneath them. A pair of .channel beams 30 are secured to the overhead beam 120i the main frame andere spaced apartby Adownwardly extending channel beamsl 31-and32,

therlatter being rigidly fastenedto the beamsBO vand terminating at their lower Aends between -the S5 iramemembers 26,` and 27 ci the straightening device.A Pivotally secured to the lower end of g the beam 30 isga pair of linkV bars 33 Vwhich-extend substantially horizontally andare connected M.By ,this arrangement of the, link V,bars v'33` and pendant bearns 31, the YframeV of etherstraighten- Aing devicev is allowed freedom for substantially verticalmovement butpis'prevented from moy*v zing` longitud" .of the vlumber Y a guide for vertical movementof the rear end of 4,the frame.V v v y in thedirectionof movement -The pendant beamv 32 constitutes rixedon vthe horizontal shaft I25,15 atrae@ drum`v35 vand cam 36. To V,engagethe periphery `of 100 the brake drum, ka brakeV brandl 37 is provided. ,At one end thisband is secured to anwangle bar 38 constituting; part vof theg frame and; ithe` other end of the band-has securedthereto-a ilange memvertical rod 40. The lowerendrof the rod flOhas Y a -head engaging the bar 38 andfsaid rod extends above the member 39 and has a spring 41 coniined thereon Ato normally actuate the brake bandjto shaft 42 extends parallel to the shaft 25 and is mounted in suitable bearings on the frame members 26 and 27. Pivoted on this shaft 42 is a tubular member 43 having an integral pair of l from the member 43 at opposite sides of the spring 41 to actuate a U-shaped rod 47 which passes beneath the member 39 and has its ends bent outward to engage the arms 46 in suitable perforations therein. It will be understood that the cam 36 is Vformed with a projection arranged to actuate the roller 45 periodically, so that the brake band 37 is loosened by the action of the arms 44 and 46 and rod 47 in raising the member 39 against the spring 41. The lower reach of the chain 19 is prevented from bending upward, out of a straight line, by a guide bar 49 of angular cross section.

In operation, a shaft 17a for supporting and driving the sprocket wheels 17, is driven by suitable connections with a motor. A sprocket wheel 48 on one end of theshaft 17a may be employed vfor the power connection so that the chains 16 are continuously driven in the direction indicated vby arrows in Figs. 2 and 4. Each piece of lumber to be trimmed is laid across the skids 13 at the receiving side of the machine and is picked up and carried along the skids by a row of the lugs 18 on the chain 16. Three of the straightening devices are preferably used, as indicated in- Fig. 1, one of these devicespeing located near the middle point of the beam l2 and the other two near the trimming saws 15. The several straightening devices are disposed in alignment longitudinally of the lumber so that a set of three of the lugs attached to the chains 19 engages each piece of the lumber. As a piece of lumber is carried beneath the chains 19 it strikes a set of the shoes 23 on the lugs 22 and actuates the chains 19, together with the sprocket wheels 20 and 21, brake Vdrums 35 and cams 36. During a greater part of the movement of each chain 19 in engagement with the lumber the brake band is held in operative relation to the drum 35 by the spring 4l so that the straightening device has a forceful retarding or backward thrust on each piece of lumber. This backward thrust is suicient to straighten pieces of lumber `which are bowed longitudinally and is sodistributedby the three devices that it is effective whether the bow of a particular piece is away from the lugs 18 near the middle of a row, or near the end lugs 18. The straightening force is applied to each piece vduring its travel past the saws but as theV piece approaches the end of the lower reach of the chain 19, the cam 36 reaches a position where it actuates the roller 45 and, through the connections with the brake band, releases the brake against the spring 41. This allows the chain 19 to move freely while one piece of lumber is passing out of engagement with the lugs 22 and while the succeeding piece is moving into proper engagement with the succeeding lugs 22. The weight of the straightening device is sufficient to prevent the lumber from moving laterally or vertically out of the path of the lugs 18 and 22 and, as hereinbefore described, the frame supporting the chain 19 is movable vertically to permit the passage of pieces of lumber of various thicknesses between the lower reach of said chain and top of the skids 13.

Obviously the operation of straightening the lumber takes place simultaneously with the trimming and does not substantially increase the cost of manufacture. Our device is adapted for use with machines other than that illustrated and has been used successfully in the manufacture of lumber which is marked at regularly spaced intervals, as by foot and inch marks extending transverse the greatest dimension.

Having described our invention, what we claim as new and desire to protect by Letters Patent is:

1. A straightening device for lumber having in combination means for moving pieces of lumber edgeways and in spaced relation to each other along a determined path, an endless chain having one of its reaches extending in parallel relation to the direction of'movement of the lumber, lugs projecting from said chain to engage the front edges ofsaid pieces and friction means for retarding said chain to forcibly straighten the lumber edgeways by rearward bending of the same, said chain'being arranged tobe actuated by engagement withnthe moving lumber.

2. A straightening machine for lumber having in combination means for moving lumber along a determined path, a retarding device extending in parallel relation to the direction of movement of the lumber, means projecting from said device in the path of the lumber, friction means for retarding said device to forcibly straighten the lumber, said -device being arranged to be actuated by engagement with the moving lumber and means forV actuating said friction means to reduce the friction.

3. A lumber Vstraightening device having in combination a lumber receiving table, means for moving lumber upon said table in a direction transverse the greatest dimension of the lumber, a plurality of endless chains having lugs projecting into the path of the lumber on said table, said chain being movable by engagement of said lugs with the lumber, a brake for retarding each of said chains and means for periodically actuating said brakes to allow free movement of said chains.

4. In a lumber straightening device,'.a pair of sprocket wheels,an endless chain trained on said wheels, spaced projections on said chain for engaging lumber, a shaft operatively connected to Vone of said sprocket wheels, a brake drum on said shaft, a friction band on said drum, means for actuating said band to grip said drum, a cam on said shaft and means operatively connecting said cam to said friction band for periodically releasing said drum.

by said chains may be actuated by engagement with the lumber, friction means operatively connected to each of said chains, spring means for actuating said friction means to retard. said chains, a cam operatively connected to each of said chains and means operatively connecting said cams to said friction means for periodically releasing said chains.

6. In a machine for forcibly straightening curved pieces of lumber, a conveyer adapted .to forcibly move separate pieces of lumber along a determined path, means fixed on said conveyer for engaging the rear of each piece of lumber, said engaging means extending in a straight line perpendicular'to the direction of movement of the conveyer, a friction retarded device movable a substantial distance along said path adjacent to said conveyer and a projection onsaid retarded device adapted to positively engage the front surface of a piece of lumber on said conveyer, said projection being movable a substantial distance along said conveyer to bend the lumber rearwardly and thereby straighten the same.

7. In a machine for forcibly sraightening curved pieces of lumber, a conveyer having lumber-engaging means spaced longitudinally of the conveyer to advance pieces of lumber in parallel, widely spaced relation to each other along the determined path, a retarding device movable a substantial distance along said path adjacent to said conveyer and a lug projecting from said retard ing device into the path of said lumber, said lug being arranged to engage a piece of lumber on said conveyer to bend it rearwardly and being movable in operative position along said conveyer a distance not greater than the spacing of said lumber-engaging means along the conveyer.

8. A lumber straightening device having in combination, a conveyer for moving pieces of lumber in spaced, parallel relation to each other 'along a determined path, a plurality of retarding devices spaced apart longitudinally of the lumber and movable in parallel relation to the direction of movement of said conveyer, each of said retarding devices having a lug projecting to positively engage the front surface of a piece of lum ber on said conveyer and said retarding devices being independently mounted so that movement of one of them does not affect the movement of another of said devices and power-driven means for actuating said conveyer to forcibly advance the pieces of lumbersuccessively into engage1 ment with said retarding devices.

9. In a machine for forcibly straightening curved pieces of lumber, a plurality of conveyer chains each having a reach extending in a common plane with a reach of the other chains, lugs fixed on said chains for engaging the rear of each piece of lumber, said lugs extending in a straight line perpendicular to the direction of movement of the chains, a friction retarded device movable a substanial distance in parallel relation to said reaches of the chains, a projection on said re tarded device adapted to positively engage the front surface of a piece of lumber carried by said chains and power-driven means for actuating bend the lumber rearwardly and thereby straighten the same.

10. Amachinehaving in combination, means for treating lumber and means for forcibly straightening curved pieces of lumber during the operation of said treating means, said straightening means comprising aconveyer adapted to move pieces of lumber in spaced, parallel relation to each other along a determined path to and from said lumber treating means, a retarding device movable asubstantial distance along said path adjacent to said conveyer and a projection on said retarding deviceformed to positively engage a piece of lumber onl said conveyer and movable a substantial distance along said conveyer to bend the lumber rearwardly and to retain the lumber in rearwardly bent position during the operation of said treating means.

l1. A machine having in combination, means for trimming the ends of lumber and means for forcibly straightening laterally curved pieces of lumber during the operation of said trimming means, said straightening means comprising a conveyer adaptedto move pieces of lumber in spaced, parallel relation to each other along a determined vpath, adjacent to said trimming means, a retarding device movable a substantial distance along said path adjacent to said conveyer and a projection on said retarding device formed to positivelyl engage the front surfaces of pieces of lumber on said conveyer and movable a substantial distance along said conveyer to bend the lumber rearwardly and to retain the lumber in rearwardly bent position during the operation of said trimming means. y 12. In a machine for forcibly straightening laterally bent pieces of lumber, a conveyer adapted to forcibly move lumber edgeways along a deter-l mined path, means iixed on said conveyer for engaging the rear vedge of the lumber and extending in a straightline perpendicular to the direction of movement of the conveyer, a friction retarded device movable arsubstantialA distance along said path adjacent to said conveyer and means on said retarded device adapted to positively engage a piece of lumber on said conveyer, said engaging means being movable a substantial distance along said conveyer to bend the lumber rearwardly and thereby'retainrthe same in straightened form during a substantial por-l tion of the travel of said conveyer.

HENRY H. PAYZANT. PAUL F. LUETH.

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